In a large non-stick skillet, melt butter, and add the sausage and cook over medium heat until golden brown. If using pre-cooked kielbasa, chop and saute for 5 minutes or until heated through.
Add the onion, and saute for 5 minutes, until onions are clear.
Spoon sausage and onion into a large stock pot, and add the chicken broth, tomato sauce, and water.
Add flour to skillet drippings, and stir to cook, about 2 minutes. Add to stock pot, stir and bring to a boil.
Add Italian seasoning, oregano, brown sugar, garlic salt, and pepper, and turn heat to low and simmer for 30 minutes.
Add the basil, and minced garlic.
Add the Tortellini and cook for 10 minutes. Add the kale and cream, and cook for another 10 minutes, or until kale is soft.
Let the soup simmer for another 30 minutes, stirring occasionally. If you really can't wait for it to simmer, feel free to eat it at this point! Stir well, and serve in bowls with crusty bread. Enjoy!